text: 'use strict';
  const LL = require ('../Data-Structure/linkedList/linked-list');
  const Node = LL.Node;
  const LinkedList = LL.LinkedList;
  function zipLists (ll1,ll2){
    if (ll1.head === null){
      return ll2.head;
    }
    if (ll2.head ===null){
      return ll1.head;
    }
  
    let ll2Node = ll2.head;
    let ll1Node = ll1.head;
  
    while (ll2Node.next && ll1Node.next ){
  
      ll1.insertAfter(ll1Node.value,ll2Node.value);
      console.log(ll1.toString());
  
      ll2Node = ll2Node.next;
      ll1Node = ll1Node.next.next;
    }
    while (ll2Node.next){
      ll1.append(ll2Node.value);
      ll2Node = ll2Node.next;
      ll1Node = ll1Node.next ;
  
    }
  
    if (!ll2Node.next && !ll1Node.next){
  
      ll1.append(ll2Node.value);
  
  
    }else{
      ll1.insertAfter(ll1Node.value,ll2Node.value);
  
    }
  
  
  
  
    console.log(ll2Node);
  
    return ll1.head;
  
  }
  module.exports = zipLists;
  